U.S. patent number 10,794,759 [Application Number 16/418,453] was granted by the patent office on 2020-10-06 for optical detection sensor.
This patent grant is currently assigned to BOE TECHNOLOGY GROUP CO., LTD., FUZHOU BOE OPTOELECTRONICS TECHNOLOGY CO., LTD.. The grantee listed for this patent is BOE TECHNOLOGY GROUP CO., LTD., FUZHOU BOE OPTOELECTRONICS TECHNOLOGY CO., LTD.. Invention is credited to Xi Chen, Hao Cheng, Yanfei Chi, Guichun Hong, Yawen Huang, Dahai Li, Zongxiang Li, Jiamin Liao, Linlin Lin, Yao Liu, Zuwen Liu, Yaochao Lv, Xinmao Qiu, Changhong Shi, Wenchang Tao, Jin Wang, Zhendian Wu, Zhixiao Yao, Min Zhou, Zihua Zhuang.
United States Patent |
10,794,759 |
Cheng , et al. |
October 6, 2020 |
Optical detection sensor
Abstract
An optical detection sensor is disclosed. The optical detection
sensor includes a converter configured to receive non-visible
light, convert the non-visible light into visible light, and emit
the visible light; and a visible light solid-state image sensor.
The converter is located on a light incident side of the visible
light solid-state image sensor, and the visible light solid-state
image sensor is configured to receive the visible light to generate
an electron flow, convert information of the electron flow into
data information, and output the data information.
Inventors: |
Cheng; Hao (Beijing,
CN), Chi; Yanfei (Beijing, CN), Chen;
Xi (Beijing, CN), Yao; Zhixiao (Beijing,
CN), Li; Zongxiang (Beijing, CN), Liao;
Jiamin (Beijing, CN), Tao; Wenchang (Beijing,
CN), Wu; Zhendian (Beijing, CN), Li;
Dahai (Beijing, CN), Lin; Linlin (Beijing,
CN), Hong; Guichun (Beijing, CN), Liu;
Yao (Beijing, CN), Liu; Zuwen (Beijing,
CN), Wang; Jin (Beijing, CN), Qiu;
Xinmao (Beijing, CN), Shi; Changhong (Beijing,
CN), Lv; Yaochao (Beijing, CN), Zhuang;
Zihua (Beijing, CN), Zhou; Min (Beijing,
CN), Huang; Yawen (Beijing, CN) |
Applicant: |
Name |
City |
State |
Country |
Type |
FUZHOU BOE OPTOELECTRONICS TECHNOLOGY CO., LTD.
BOE TECHNOLOGY GROUP CO., LTD. |
Fuzhou, Fujian
Beijing |
N/A
N/A |
CN
CN |
|
|
Assignee: |
FUZHOU BOE OPTOELECTRONICS
TECHNOLOGY CO., LTD. (Fuzhou, CN)
BOE TECHNOLOGY GROUP CO., LTD. (Beijing, CN)
|
Family
ID: |
1000005096785 |
Appl.
No.: |
16/418,453 |
Filed: |
May 21, 2019 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20200011730 A1 |
Jan 9, 2020 |
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Foreign Application Priority Data
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Jul 5, 2018 [CN] |
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2018 1 0730683 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04N
5/379 (20180801); H01L 27/14692 (20130101); H01L
27/14645 (20130101); H04N 5/3696 (20130101); G01J
1/42 (20130101); H01L 27/14649 (20130101); H01L
31/105 (20130101); H01L 27/14689 (20130101) |
Current International
Class: |
H01L
27/146 (20060101); G01J 1/42 (20060101); H04N
5/369 (20110101); H01L 31/105 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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101256097 |
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Sep 2008 |
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CN |
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103178076 |
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Jun 2013 |
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CN |
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103180968 |
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Jun 2013 |
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CN |
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Other References
The First Chinese Office Action dated Aug. 29, 2019; Appln. No.
201810730683.4. cited by applicant.
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Primary Examiner: Dagnew; Mekonnen D
Claims
What is claimed is:
1. An optical detection sensor, comprising: a converter configured
to receive non-visible light, convert the non-visible light into
visible light, and emit the visible light; and a visible light
solid-state image sensor, wherein the converter is located on a
light incident side of the visible light solid-state image sensor,
and the visible light solid-state image sensor is configured to
receive the visible light to generate an electron flow, convert
information of the electron flow into data information, and output
the data information, the converter comprises an organic light
emitting layer, an anode, and a cathode; the anode and the cathode
are respectively located on both sides of the organic light
emitting layer, the anode is configured to absorb photons of the
non-visible light and generate photo-generated carriers injected
into the organic light emitting layer, and the anode comprises a
heterojunction photo transistor including an emitter, a base and a
collector which are sequentially stacked, the collector is located
on a side of the base and the emitter close to the photodiode, and
the collector is configured to inject the photo-generated carriers
into the organic light emitting layer, so that the organic light
emitting layer emits the visible light.
2. The optical detection sensor according to claim 1, wherein the
visible light solid-state image sensor comprises a photodiode, a
thin film transistor, and a read out integrated circuit; the
converter is located on a light incident side of the photodiode,
and the photodiode is configured to absorb the visible light
emitted by the converter and generate the electron flow; the thin
film transistor is connected with the photodiode and configured to
receive the electron flow in the photodiode; and the read out
integrated circuit is connected with the thin film transistor and
configured to read the information of the electron flow from the
thin film transistor, convert the information of the electron flow
into the data information, and output the data information.
3. The optical detection sensor according to claim 2, wherein the
photodiode is a PIN photodiode.
4. The optical detection sensor according to claim 2, wherein the
visible light solid-state image sensor further comprises a control
line and a data line, the control line is connected with a gate
electrode of the thin film transistor to turn on/off the thin film
transistor, the data line is connected with one of a source
electrode and a drain electrode of the thin film transistor to
receive the electron flow of the photodiode, and the other one of
the source electrode and the drain electrode of the thin film
transistor is connected with the photodiode.
5. The optical detection sensor according to claim 4, wherein the
read out integrated circuit comprises an analog-to-digital
converter, and the read out integrated circuit is configured to
read a charge change amount on the data line, convert the charge
change amount into a low voltage differential signal by the
analog-to-digital converter, and output the low voltage
differential signal.
6. The optical detection sensor according to claim 2, wherein the
visible light solid-state image sensor further comprises a light
shielding layer located on a side of the thin film transistor
facing the converter to prevent the visible light from irradiating
the thin film transistor.
7. The optical detection sensor according to claim 1, wherein the
anode further comprises a metal electrode layer on a side of the
heterojunction photo transistor facing the organic light emitting
layer.
8. The optical detection sensor according to claim 1, wherein the
emitter of the heterojunction photo transistor comprises p-type
indium phosphide, the base of the heterojunction photo transistor
comprises n-type indium gallium arsenide, and the collector of the
heterojunction photo transistor comprises p-type indium gallium
arsenide.
9. The optical detection sensor according to claim 1, wherein the
visible light solid-state image sensor comprises a charge coupled
device or a complementary metal-oxide-semiconductor image
sensor.
10. The optical detection sensor according to claim 1, wherein the
non-visible light received by the converter comprises infrared
light.
11. The optical detection sensor according to claim 1, wherein the
visible light converted by the converter comprises green light.
Description
The present application claims priority of China Patent application
No. 201810730683.4 filed on Jul. 5, 2018, the content of which is
incorporated in its entirety as portion of the present application
by reference herein.
TECHNICAL FIELD
At least one embodiment of the present disclosure relates to an
optical detection sensor.
BACKGROUND
With the development and application of optoelectronic technology,
photoelectric conversion sensors with mature technology have been
widely applied.
At present, a charge coupled device (CCD) and a complementary
metal-oxide-semiconductor (CMOS) sensor are both made of
semiconductor materials with high sensitivity, and an optical
signal can be converted into an electrical signal by the charge
coupled device or the complementary metal-oxide-semiconductor
sensor, the electrical signal can be read and applied.
SUMMARY
At least one embodiment of the present disclosure provides an
optical detection sensor. The optical detection sensor includes a
converter and a visible light solid-state image sensor. The
converter is configured to receive non-visible light, convert the
non-visible light into visible light, and emit the visible light;
and the converter is located on a light incident side of the
visible light solid-state image sensor, and the visible light
solid-state image sensor is configured to receive the visible light
to generate an electron flow, convert information of the electron
flow into data information, and output the data information.
For example, the visible light solid-state image sensor includes a
photodiode, a thin film transistor, and a read out integrated
circuit. The converter is located on a light incident side of the
photodiode, and the photodiode is configured to absorb the visible
light emitted by the converter and generate the electron flow; the
thin film transistor is connected with the photodiode and
configured to receive the electron flow in the photodiode; and the
read out integrated circuit is connected with the thin film
transistor and configured to read the information of the electron
flow from the thin film transistor, convert the information of the
electron flow into the data information, and output the data
information.
For example, the converter includes an organic light emitting
layer, an anode, and a cathode; the anode and the cathode are
respectively located on both sides of the organic light emitting
layer, the anode is configured to absorb photons of the non-visible
light and generate photo-generated carriers injected into the
organic light emitting layer.
For example, the anode includes a heterojunction photo transistor
including an emitter, a base and a collector which are sequentially
stacked, the collector is located on a side of the base and the
emitter close to the photodiode, and the collector is configured to
inject the photo-generated carriers into the organic light emitting
layer, so that the organic light emitting layer emits the visible
light.
For example, the anode further includes a metal electrode layer on
a side of the heterojunction photo transistor facing the organic
light emitting layer.
For example, the emitter of the heterojunction photo transistor
includes p-type indium phosphide, the base includes n-type indium
gallium arsenide, and the collector includes p-type indium gallium
arsenide.
For example, the visible light solid-state image sensor includes a
charge coupled device or a complementary metal-oxide-semiconductor
image sensor.
For example, the photodiode is a PIN photodiode.
For example, the visible light solid-state image sensor further
includes a control line and a data line, the control line is
connected with a gate electrode of the thin film transistor to turn
on/off the thin film transistor, the data line is connected with
one of a source electrode and a drain electrode of the thin film
transistor to receive the electron flow of the photodiode, and the
other one of the source electrode and the drain electrode of the
thin film transistor is connected with the photodiode.
For example, the read out integrated circuit includes an
analog-to-digital converter, and the read out integrated circuit is
configured to read a charge change amount on the data line, convert
the charge change amount into a low voltage differential signal by
the analog-to-digital converter, and output the low voltage
differential signal.
For example, the non-visible light received by the converter
includes infrared light.
For example, the visible light converted by the converter includes
green light.
For example, the visible light solid-state image sensor further
includes a light shielding layer located on a side of the thin film
transistor facing the converter to prevent the visible light from
irradiating the thin film transistor.
BRIEF DESCRIPTION OF THE DRAWINGS
In order to clearly illustrate the technical solution of
embodiments of the present disclosure, the drawings of the
embodiments will be briefly described in the following, it is
obvious that the drawings in the description are only related to
some embodiments of the present disclosure and not limited to the
present disclosure.
FIG. 1A is a schematic structural diagram of an optical detection
sensor provided by an embodiment of the present disclosure;
FIG. 1B is a schematic structural diagram of an optical detection
sensor provided by an embodiment of the present disclosure;
FIG. 2 is a schematic structural diagram of a converter in an
optical detection sensor provided by an embodiment of the present
disclosure;
FIG. 3 is a schematic structural diagram of another converter in an
optical detection sensor provided by an embodiment of the present
disclosure;
FIG. 4 is a schematic structural diagram of a photodiode in an
optical detection sensor provided by an embodiment of the present
disclosure;
FIG. 5 is a schematic diagram of a connection relationship among a
photodiode, a thin film transistor, and a read out integrated
circuit in an embodiment of the present disclosure; and
FIG. 6 is a schematic structural diagram of another optical
detection sensor provided by an embodiment of the present
disclosure.
DETAILED DESCRIPTION
In order to make objects, technical details and advantages of the
embodiments of the present disclosure apparent, the technical
solutions of the embodiments will be described in a clearly and
fully understandable way in connection with the drawings related to
the embodiments of the present disclosure. Apparently, the
described embodiments are just a part but not all of the
embodiments of the present disclosure. Based on the described
embodiments herein, those skilled in the art can obtain other
embodiment(s), without any inventive work, which should be within
the scope of the present disclosure.
Unless otherwise defined, all the technical and scientific terms
used herein have the same meanings as commonly understood by one of
ordinary skill in the art to which the present disclosure belongs.
The terms "first," "second," etc., which are used in the present
disclosure, are not intended to indicate any sequence, amount or
importance, but distinguish various components. Also, the terms
"comprise," "comprising," "include," "including," etc., are
intended to specify that the elements or the objects stated before
these terms encompass the elements or the objects and equivalents
thereof listed after these terms, but do not preclude the other
elements or objects.
In the research, the inventor(s) of the present application notices
that infrared light of which wavelength is located between that of
visible light and microwave has a great application prospect in
military industry, medical industry and photovoltaic industry.
However, it is difficult for the existing CCD, CMOS and other
sensors to capture light with a wavelength greater than 1 micron
(.mu.m) in infrared waveband. Thus, an application range of such
sensors is limited.
An optical detection sensor provided by an embodiment of the
present disclosure includes a converter and a visible light
solid-state image sensor. The converter is located on a light
incident side of the visible light solid-state image sensor, and
the visible light solid-state image sensor is configured to receive
visible light to generate an electron flow, convert information of
the electron flow into data information, and output the data
information. In the optical detection sensor provided by the
embodiment of the present disclosure, the converter is combined
with the visible light solid-state image sensor, and non-visible
light received by the converter serving as a non-visible light
conversion device is converted into visible light, and the visible
light solid-state image sensor converts the visible light obtained
from the converter into a digital signal and outputs the digital
signal, thus achieving a function of converting non-visible light
having infrared waveband, near infrared waveband and other
wavebands into a digital signal. Therefore, a problem that an
application range of CCD, CMOS and other sensors is limited due to
the difficulty in capturing light with a wavelength greater than 1
.mu.m in the infrared waveband can be solved, so that the optical
detection sensor provided by the embodiment of the present
disclosure can be widely applied in industries such as military
industry, medical industry and photovoltaic industry.
Hereinafter, the optical detection sensor provided by at least one
embodiment of the present disclosure will be described below with
reference to the accompanying drawings.
FIG. 1A is a schematic structural diagram of an optical detection
sensor provided by at least one embodiment of the present
disclosure. The optical detection sensor 10 provided in the present
embodiment may include a converter 110 and a visible light
solid-state image sensor 1234. The converter 110 is located on a
light incident side of the visible light solid-state image sensor
1234, and the visible light solid-state image sensor 1234 is
configured to receive visible light to generate an electron flow,
convert information of the electron flow into data information, and
output the data information. According to the embodiment of the
present disclosure, by combining the converter serving as a
non-visible light conversion device with the visible light
solid-state image sensor, a problem that an application range of
CCD, CMOS and other sensors is limited due to the difficulty in
capturing light with a wavelength greater than 1 .mu.m in the
infrared waveband can be solved, so that the optical detection
sensor provided by at least one embodiment of the present
disclosure can be widely applied to industries such as military
industry, medical industry, and photovoltaic industry.
For example, the visible light solid-state image sensor 1234 may
include a charge coupled device or a complementary
metal-oxide-semiconductor image sensor.
For example, as illustrated by FIG. 1B, the visible light
solid-state image sensor 1234 may include a photodiode 120, a thin
film transistor (TFT) 130, and a read out integrated circuit (ROIC)
140.
In at least one embodiment of the present disclosure, the converter
110 can emit the visible light converted by the converter 110, the
visible light can be received by the photodiode 120, and an
internal of the photodiode 120 excites electrons after absorbing
the visible light. For example, the photodiode 120 may include a P
layer and an N layer, and electrons generated by excitation cannot
pass through the P layer, that is, electrons flow out from the N
layer of the photodiode 120 to form an electron flow out from the
photodiode 120. After the electron flow of the photodiode 120
reaches the thin film transistor 130, the read out integrated
circuit 140 connected with the thin film transistor 130 reads the
information of the electron flow from the thin film transistor 130,
converts a signal of the electron flow as read into a digital
signal, and outputs the digital signal, thus achieving an indirect
detection sensor configured to detect non-visible light.
The optical detection sensor provided by at least one embodiment of
the present disclosure combines modules such as a converter, a
photodiode, a thin film transistor, and a read out integrated
circuit. The converter serves as a non-visible light conversion
device to convert non-visible light as received into visible light,
the photodiode generates an electron flow after absorbing the
visible light obtained from the converter, and after the electron
flow reaches the thin film transistor, the read out integrated
circuit reads the electron flow in the thin film transistor,
converts information of the electron flow as read into digital
information, and outputs the digital information. According to the
optical detection sensor provided by the embodiment of the present
disclosure, a function of converting non-visible light having
infrared waveband, near infrared waveband and other wavebands into
a digital signal can be realized by reasonably configuring the
abovementioned combination mode, so that the optical detection
sensor can be widely configured into industries such as military
industry, medical industry, and photovoltaic industry, and the
problem that the application range of common CCD, CMOS and other
sensors is limited due to the difficulty in capturing light with a
wavelength greater than 1 .mu.m in the infrared waveband can be
solved.
For example, as illustrated by FIG. 1B, the converter 110 is
located on a light incident side of the photodiode 120, and the
photodiode 120 is configured to absorb the visible light emitted by
the converter 110 (arrows in FIG. 1 indicate the visible light
emitted by the converter) and generate an electron flow, which is a
current formed by directional movement of free electrons in space.
The thin film transistor 130 is connected with the photodiode 120
and configured to receive the electron flow in the photodiode 120.
The read out integrated circuit 140 is connected with the thin film
transistor 130, and is configured to read information of the
electron flow from the thin film transistor 130, convert the
information of the electron flow as read into data information, and
output the data information.
For example, the converter 110 may include a photosensitive
material to receive non-visible light, such as infrared light and
near infrared light, and may convert the non-visible light as
received into visible light and emit the visible light, so that the
photodiode 120 located on a light exit side of the converter 110
can receive visible light.
For example, in practical application, the non-visible light
absorbed by the converter 110 may be infrared light that is
harmless to human body, including, for example, near infrared
light, middle infrared light, and far infrared light. The following
embodiments of the present disclosure will be described by taking a
case where the converter 110 absorbs near infrared light as an
example. The converter 110 can convert the near infrared light
absorbed by the converter 110 into green light with a wavelength of
about 520 nanometers (nm), but the embodiments of the present
disclosure are not limited thereto.
For example, FIG. 2 is a schematic structural diagram of a
converter in an optical detection sensor provided by an example of
at least one embodiment of the present disclosure. As illustrated
by FIG. 2, the converter 110 provided by the embodiment of the
present disclosure may include an organic light emitting layer 111,
an anode 112, and a cathode 113, the anode 112 and the cathode 113
are located on both sides of the organic light emitting layer
111.
For example, the organic light emitting layer 111 may include a
light emitting layer, a hole transport layer located on a side of
the light emitting layer close to the anode 112, and an electron
transport layer located on a side of the light emitting layer close
to the cathode 113. The anode, the organic light emitting layer,
and the cathode constitute an organic light emitting diode.
For example, as illustrated by FIG. 2, near infrared light may be
received by the anode 112 to generate photo-generated carriers. For
example, a voltage of, for example, a bias voltage of 12 volts (V)
may be applied to the anode 112 and the cathode 113 located on both
sides of the organic light emitting layer 111. Under the action of
electric field, the anode 112 generates holes by receiving the
near-infrared light 101, and the cathode 113 generates electrons.
The holes injected into the organic light emitting layer 111 by the
anode 112 are combined with the electrons injected into the organic
light emitting layer 111 by the cathode 113 in the light emitting
layer of the organic light emitting layer 111, thereby emitting
visible light 102, for example, the visible light 102 may be green
light with a wavelength of about 520 nm.
For example, FIG. 3 is a schematic structural diagram of a
converter in an optical detection sensor provided by another
example of at least one embodiment of the present disclosure. As
illustrated by FIG. 3, the anode 112 of the converter 110 in the
embodiment of the present disclosure may include a heterojunction
photo transistor (HPT) 112a and a metal electrode layer 112b. The
heterojunction photo transistor 112a may include an emitter e, a
base b and a collector c which are sequentially connected, i.e.,
the emitter e, the base b and the collector c are sequentially
stacked. The collector c is located on a side of the base b and the
emitter a close to the photodiode, and the collector c is
configured to inject photo-generated carriers into the organic
light emitting layer 111 so that the organic light emitting layer
111 emits the visible light 102.
For example, the heterojunction photo transistor 112a has an
internal gain and can achieve an amplification of photocurrent. The
base b of the heterojunction photo transistor 112a absorbs photons
of the near-infrared light 101 to generate photo-generated
carriers. Under the action of an applied voltage, a base-emitter
junction is forward biased and a base-collector junction is reverse
biased. The heterojunction photo transistor 112a operates in an
amplification region, and photocurrent as generated is amplified,
outputted at the collector c of the heterojunction photo transistor
112a, and injected into the organic light emitting layer 111.
For example, the base b and the collector c in the heterojunction
photo transistor 112a absorb non-visible light to generate
electron-hole pairs, electrons are accumulated in the base b, so
that a forward voltage between the base b and the emitter e is
increased, and a reverse voltage between the base b and the
collector c is increased, thereby injecting holes into the organic
light emitting diode 111. Therefore, the heterojunction photo
transistor in the embodiment of the present disclosure functions as
an anode of the organic light emitting diode.
For example, as illustrated by FIG. 3, the emitter e of the
heterojunction photo transistor 112a may be p-type indium phosphide
(P-InP), the base b may be n-type indium gallium arsenide
(N-InGaAs), and the collector c may be p-type indium gallium
arsenide (P-InGaAs). The embodiment of the present disclosure will
be described by taking a case where the heterojunction photo
transistor 112a is a PNP type heterojunction photo transistor 112a
as an example.
For example, in a manufacturing process of the heterojunction photo
transistor 112a, the abovementioned PNP-type heterojunction photo
transistor 112a can be formed by using P-InP as a substrate and
epitaxially growing P-InGaAs and N-InGaAs. The P-InP, the N-InGaAs,
the P-InGaAs and the organic light emitting layer which are
connected in series form a main structure of the heterojunction
photo transistor 112a in the embodiment of the present disclosure.
In the main structure, the base b (N-InGaAs) and the collector c
(P-InGaAs) generate carriers after absorbing near infrared light.
Under the action of an applied voltage (for example, 12V),
electrons are accumulated at the base b (N-InGaAs), so that a
forward voltage between the base b (N-InGaAs) and the emitter e
(P-InP) is increased, and a reverse voltage between the base b
(N-InGaAs) and the collector c (P-InGaAs) is increased (i.e., the
base-emitter junction of the heterojunction photo transistor 112a
is forward biased and the base-collector junction is reverse
biased), resulting in an effect of current gain. The heterojunction
photo transistor 112a operates in an amplification region, and
photocurrent as generated is amplified and outputted at the
collector c, and holes are injected into the organic light emitting
diode 111. The PNP type heterojunction photo transistor 112a is
mainly configured to absorb near infrared light with a wavelength
range of 0.7 to 2.5 .mu.m.
It should be noted that the structure of the heterojunction photo
transistor 112a is used as the anode 112 of the organic light
emitting diode, and a metal electrode layer 112b is further
arranged between the organic light emitting layer 111 and the anode
112 of the organic light emitting diode. The metal electrode layer
112b is favorable for carrier transmission and reduces a turn-on
voltage of the heterojunction photo transistor 112a.
For example, FIG. 4 is a schematic structural diagram of a
photodiode in an optical detection sensor according to an
embodiment of the present disclosure. The photodiode 120 in the
embodiment of the present disclosure may adopt a PIN photodiode
120, which may include a P layer 121, an I layer 122, and an N
layer 123 which are sequentially stacked. Herein, the I layer 122
is an intrinsic semiconductor layer or a doped layer of an
intrinsic semiconductor with a low doping concentration. The I
layer 122 is relatively thick and occupies almost an entire
depletion layer, so most of the light incident through the
transparent electrode 130 of the photodiode 120 is absorbed in the
I layer 122 and generates a large number of electron-hole
pairs.
For example, after the PIN photodiode 120 is configured to absorb
non-visible light, the I layer 122 excites electrons, and the
electrons flow out of the N layer 123 to form an electron flow.
In the embodiment of the present disclosure, visible light (e.g.,
green light) generated by the converter 110 is absorbed by the PIN
photodiode 120, and the I layer 122 generates photo-excited
electrons. Because the electrons cannot pass through the P layer
121, i.e., the electrons flow out of the N layer 123 to form the
electron flow.
For example, FIG. 5 is a schematic diagram of a connection
relationship among a photodiode, a thin film transistor, and a read
out integrated circuit in an embodiment of the present disclosure.
As illustrated by FIG. 5, the visible light solid-state image
sensor further includes a control line 150 and a date line 160. The
control line 150 is connected with a gate electrode of the thin
film transistor 130 to turn on/off the thin film transistor 130,
the data line 160 is connected with one of a source electrode and a
drain electrode of the thin film transistor 130 to receive the
electron flow flowing out of the photodiode 120, and the other one
of the source electrode and the drain electrode of the thin film
transistor 130 is connected with the photodiode 120.
For example, as illustrated by FIG. 5, a control circuit can
control the turn-on and turn-off of the thin film transistor 130
through the control line 150. Therefore, implementation of the thin
film transistor 130 receiving the electron flow flowing out of the
photodiode 120 can include: after the thin film transistor 130 is
turned on through the control line 150, the data line 160 receives
the electron flow flowing out of the photodiode 120, so that charge
amount of the data line 160 changes.
For example, the embodiment of the present disclosure is described
by taking a case where the photodiode 120 is a PIN photodiode as an
example. After the thin film transistor 130 is turned on, electrons
flowing out of the N layer of the PIN photodiode can pass through
the thin film transistor 130 and flow into the data line 160. Thus,
an amount of charge in the data line 160 changes.
For example, in the embodiment of the present disclosure, the read
out integrated circuit 140 may include an analog-to-digital
converter (ADC). Implementation of the read out integrated circuit
140 reading the electron flow from the thin film transistor 130,
converting information of the electron flow as read into data
information, and then outputting the data information may include:
the read out integrated circuit 140 reads a charge change amount of
the data line 160, converts the charge change amount through the
analog-to-digital converter into a low voltage differential signal
(LVDS), and outputs the low voltage differential signal. The low
voltage differential signal is a small amplitude differential
signal, which can reduce a power supply voltage and a logic voltage
swing to effectively improve data transmission speed.
FIG. 6 is a schematic structural diagram of an optical detection
sensor according to an embodiment of the present disclosure. FIG. 6
schematically shows a cross-sectional view of the converter 110,
the PIN photodiode 120 and the thin film transistor 130. As
illustrated by FIG. 6, the PIN photodiode 120 and the thin film
transistor 130 are disposed on a base substrate 103, the thin film
transistor 130 includes a gate electrode 131, a source electrode
132 and a drain electrode 133, and a portion of the source
electrode 132 and a portion of the drain electrode 133 are located
on the active layer 134. The PIN photodiode 120 is connected with
the drain electrode 133 of the thin film transistor 130 through a
bottom electrode 125 connected with the N layer of the PIN
photodiode 120, and is configured to transfer electron flow flowing
out of the N layer to the data line connected with the source
electrode 132 of the thin film transistor 130 through the thin film
transistor 130. A top electrode 124 is provided on a side of the P
layer of the PIN photodiode 120 away from the I layer of the PIN
photodiode 120. For example, the top electrode 124 may be an indium
tin oxide (ITO) electrode.
For example, as illustrated by FIG. 6, in the structure of the
optical detection sensor, a conventional insulating layer is also
provided on a side of the thin film transistor 130 close to the
converter 110, the insulating layer may include, for example, a
passivation layer 180 and a resin layer 181. A buffer layer 182 is
provided on a side of the thin film transistor 130 and the PIN
photodiode 120 close to the converter 110, and the buffer layer 182
is configured to improve adhesion of the entire structure.
For example, as illustrated by FIG. 6, the optical detection sensor
provided by the embodiment of the present disclosure is a detection
sensor with a flat panel structure, which adopts the converter 110,
the photodiode 120, the thin film transistor 130 and the read out
integrated circuit structure to achieve converting non-visible
light into a digital signal and then outputting the digital signal.
The detection sensor with a flat panel structure has a simple
structure and is easy to implement, and the flat panel structure
only occupies a relatively small physical space to achieve a
detection of the non-visible light and a signal conversion
function.
For example, in the embodiment of the present disclosure, because
the converter 110 converts non-visible light into visible light,
the visible light as converted is scattered light, i.e., the
visible light as converted has no fixed incident direction, and the
visible light outside a coverage area of the PIN photodiode 120 has
no practical effect. If the visible light irradiates on the thin
film transistor 130, the characteristics of the thin film
transistor 130 will be affected. Therefore, a light shielding layer
170 may be provided on a side of the thin film transistor 130
facing the converter 110 and in an area other than a portion of the
photodiode 120 for receiving the visible light, for example, the
light shielding layer 170 may be a shielding metal layer to shield
invalid light irradiated on the thin film transistor 130.
For example, as illustrated by FIG. 6, the optical detection sensor
further includes a bias signal line 170 located on a side of the
photodiode 124 facing the converter 110, and the bias signal line
170 is electrically connected with a top electrode 124 on a side of
the photodiode 120 close to the converter 110 to provide an applied
electric field to electrons and holes in the photodiode 120. The
embodiment of the present disclosure is described by taking a case
where the light shielding layer is a part of the bias signal line
as an example, but is not limited thereto, and the light shielding
layer and the bias signal line may also be separated
structures.
Although the disclosed embodiments of the present disclosure have
been described above, the above description is only embodiments for
facilitating understanding of the present disclosure and is not
intended to limit the present disclosure. Any person skilled in the
art to which this disclosure belongs may make any modifications and
changes in the form and details of implementations without
departing from the spirit and scope of this disclosure, but the
scope of patent protection of the present disclosure should still
be subject to the scope defined by the appended claims.
The following points should be noted:
(1) The accompanying drawings in the embodiments of the present
disclosure only involve structures relevant to the embodiments of
the present disclosure, and other structures may refer to the prior
art.
(2) The features in the same embodiment or different embodiments of
the present disclosure can be mutually combined without
conflict.
The foregoing is only the embodiments of the present disclosure and
not intended to limit the scope of protection of the present
disclosure, and the protection scope of the present disclosure
should be based on the protection scope of the appended claims.
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